Receiver heat loss efficiency formula in physical trough

The total loop conversion efficiency used in the Solar Field is the product of the loop optical efficiency and the receiver heat loss efficiency. I understand the optical efficiency to be the absorbed power/ incident power, and the receiver heat loss efficiency would then be the (absorbed power - heat loss)/ absorbed power. But, judging by the total loop conversion efficiency result, SAM seems to calculate the heat loss efficiency as (absorbed power - heat loss)/ incident power. This does not seem correct, and would give an incorrect value for the total loop conversion efficiency. Am I mistaken?

Hello,

Your observation is correct. The estimate of the total loop efficiency shown in the user interface is higher than you would expect because of an overestimate of the thermal efficiency. We are investigating this and will address the issue in the next version of SAM.

Best regards,
Paul.